Aeroponics is the technique of growing plants by providing droplets of water, and possibly water with nutrients, to plant roots, wherein the droplets are smaller than the pore size of the roots.
Water, and nutrient enriched water, are absorbed by a plant's roots, wherein the pores of a given root typically average around 50 microns in diameter, down to about 5 microns. Thus a droplet of 50 microns or less may fit inside a root pore and be attracted into the pore by a van de Waals force without requiring additional energy from the plant.
An aeroponic growth system generally comprises a system for delivery of nutrient rich water to one or more plants, wherein the plant roots are exposed to a nutrient-rich water mist comprising droplets of an appropriate size. The system may be outdoors, in a green house, or within a facility that includes provision of light for plant growth. The water may be reclaimed as it condenses and recirculated or it may be discharged.
Aeroponic growth systems implement a variety of means for providing water and nutrients to plant roots. In one example, a mist of droplets may be created by a high pressure pump providing water through a very small orifice, thus creating the droplets. The discharge orifices are generally in the vicinity of the roots within a growth chamber, intended to fill the growth cavity with a mist. Droplets so produced usually have a high average droplet size, thus are not efficiently absorbed by the roots. Accordingly more droplets must be provided and more power expended in pumping.
In other systems one or more atomizers may be placed in a reservoir. The reservoir may be located adjacent to a growth chamber. The atomizers produce a range of droplets in a mist, which are gently moved from the reservoir to the growth chamber by a fan at the upper end of the reservoir. Droplets that are light enough to be blown into the growth chamber are generally the very small ones. Though such droplets are more readily absorbed by the roots, the quantity of water or nutrients delivered per unit of time is low. Thus, the challenge is in getting enough water into the root area. The rate of delivery, noise, and the power required are problematic.
What is needed is a system for making a high yield of droplets below 50 microns in diameter wherein the entire yield of droplets is made available to the root system in an aeroponic growth system.